For the first year of its life, the iPhone 3G's GPS feature proved handy, but not spectacular, providing features such as photo geotagging and more reliable walking directions rather than the full-fledged turn-by-turn driving guidance many users had expected. Apple passed on offering the turn-by-turn feature, leaving third-party developers to spend the next year developing both iPhone-ready GPS map applications and business models to try and sell them. In June, Apple spotlighted the work of leading GPS developer TomTom, which announced plans for both an in-car GPS accessory and an iPhone app, which were believed at the time to be designed solely to work together; this week, however, the TomTom application -- actually, four separate applications -- appeared without the accessory, called the "TomTom Car Kit," and steep pricing was revealed for both the hardware and the software. Today, we're reviewing the iPhone app TomTom U.S. & Canada ($100); other software versions are available for Western Europe ($140), Australia ($80), and New Zealand ($95). The Car Kit will reportedly sell for approximately $150 in the United States and £99 in the United Kingdom; we will review it separately when it is released. In separate reviews, we also look at less expensive iPhone OS competitors to TomTom: ALK Technologies' $35 CoPilot Live 8 North America, Navigon's MobileNavigator, and Sygic's Mobile Maps US, all of which include map and point of interest databases for the United States, and most with maps of Canada, as well. In short, iPhone users now have no shortage of GPS mapping options, but they're all fairly similar to each other in major limitations -- GPS reliability and integration with other iPhone functionality -- while differing largely in interface and pricing.

Like all of the iPhone GPS solutions we’ve tested save for the subscription-based Gokivo, which downloads its map data from the Internet, TomTom U.S. & Canada requires a lengthy initial download and installation process with iTunes, but needn’t be updated with additional data in the future. TomTom’s application is slightly smaller than the 1.29GB Navigon and 1.43GB Sygic apps we’ve previously tested, while possessing similar map and point of interest content taken from TomTom’s Tele Atlas database. There has been no promise of free updated map data over time, and based on past history, we certainly wouldn’t expect it here.

Apart from Apple’s Google-aided Maps application, which makes searching for destinations incredibly easy, no company has come up with a completely streamlined, genius-level navigation interface for the iPhone OS, and TomTom US & Canada is no exception: it uses plain iPod-like white background and black text lists with colorful icons, giving you six choices on a vertical iPhone or four on a horizontal one, letting you scroll through additional choices with swipes. Though it’s obvious that TomTom designed this app for devices without multi-touch interfaces or graphics hardware as advanced as Apple’s, the swipe gestures are one of several small signs that TomTom’s app was designed to provide a slightly more iPhone-like user experience.

TomTom’s lists are intelligently ordered to provide quicker access to the most-used features: “navigate to” is the top choice, with “home” at the top of its list, favorites, addresses, recent destinations, points of interest, map points, and iPhone contacts below. Inputting addresses is very straightforward, with predictive lists appearing clearly on screen based on state, city, and street text entered with a standard iPhone keyboard, rapidly letting you manually enter addresses and choose intersections if you lack for a street number. Once you’ve selected a destination, TomTom gives you a plot of the map and a button for options, starting with its own “IQ Route” that supposedly chooses the smartest route based on actual charted driving speeds of real users, then offering alternative routing, a demonstration of the route—this runs very slow, and once crashed the app in our testing—and choices to view the route either as a list or in scrollable, zoomable map form.

Apart from that scrollable map, TomTom displays maps as substantially flat-shaded artificial 3-D or overhead 2-D auto-scrolling images, with a small pane at the bottom of the screen for data displays. Apart from using tiny zoom buttons in the upper corners of the screen, if you click on TomTom’s map, it just calls up the navigation menus; unlike CoPilot Live 8, you don’t have the ability to move around on the map when you’re in motion. You can, however, switch from 3-D to 2-D views, manually—not automatically—switch to day or night colors, and use the menu to activate a separate scrollable map like the one mentioned above; all of these features work, but they just don’t feel as smoothly integrated with one another as one might expect from an app developed for the iPhone from the ground up. TomTom compensates a little by offering multiple palette choices for day and night colors, and by offering four different U.S. English voices for navigation prompting, plus numerous foreign-language versions.

We’d describe the experience of using TomTom while driving as fine rather than great. Like the other GPS mapping applications we’ve tested, the 2-D and 3-D maps chug along slowly as you move, making chunky little perspective adjustments as your arrow-shaped vehicle moves up a street and turns corners. The maps are some of the most threadbare visually we’ve yet seen in an iPhone GPS app, using no transparency and only the most minimal of overlaid graphics while you drive. Regardless of whether you’re in wide or tall orientation—TomTom resizes its maps and interface elements for either—the screen doesn’t automatically split into panes to indicate upcoming turns, so you need to pay attention to any or all of three things: a relatively small turning indicator at the bottom center of the screen, the name of the street you’re looking for at the top, or a very simple voice prompt that tells you when to turn. On main streets, the prompts come 400 yards before a turn, with 800 yards on highways, and they don’t include street name synthesis, just “after x yards, turn right.” In these regards, the experience of using TomTom is similar to other iPhone and dedicated small GPS competitors, but on the lower end of the scale, and well below the standards of integrated in-car GPS systems. Given the high price of this app, TomTom should really have done better.

In our experience, which we will emphasize may will not be typical of most users because we went out of our way to keep the iPhone near windows rather than trying to obstruct its GPS antenna, we found the GPS signal strength sufficient under most circumstances to maintain an accurate sense of our movement on maps, as well as a sense of our driving speed that was correct to within 1 or 2mph of our actual pace. When the GPS lost signal, typically when it was moved away from a window, the maps switched to grayscale to indicate that they weren’t going to be accurate, and “Poor GPS Reception” appeared at the bottom of the screen.

More than anything else, TomTom’s Car Kit is designed to improve the GPS performance with additional GPS hardware, and though window mounting alone would help most users improve their results, it should also be noted that running the app and using the iPhone’s GPS antenna aggressively drains the 3G or 3GS’s battery—a problem common to all of the GPS software we’ve seen—so having an in-car charging solution is more or less mandatory if you’re planning to use this for any length of time.

Several other parts of the TomTom experience were worth mentioning. First, the app includes an “Advanced Planning” feature, which enables you to choose a starting point and a destination point, then select various types of options—fastest route, shortest route, avoid highways, walking, bicycling, or speed-limited route—though not a multi-destination routing system, which is either in or being added to competitors. TomTom also has a “Call POI” feature that lets you locate a point of interest and then call it on the phone, though the POI database is—as with other GPS apps we’ve tried—only decent, lacking in some places that have been open for a year or more. Finally, TomTom is capable of routing you to addresses stored in your iPhone’s Contacts database, and though it sometimes requires assistance matching your entered details to the information in its own map system, it automatically populates its screens with as much detail as you’ve provided, and makes corrections relatively easily.

Overall, TomTom U.S. & Canada is only a decent GPS app for the iPhone, priced high enough even without its optional accessory that users could easily go out and buy a standalone GPS unit, yet lacking in the sort of enhanced iPhone-specific functionality that might justify the purchase of the app instead. Unless it drops significantly in price, or dramatically improves its functionality with a free update, we wouldn’t have any major reason to recommend it over less expensive alternatives.

Editors' Note: iLounge only reviews products in "final" form, but many companies now change their offerings - sometimes several times - after our reviews have been published.
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